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What happens in an heat flow apparatus when you reduce the length of the disk?
The apparatus is this
1st level: A resistor to produce heat
2nd level: A metal disk with known thermal conductivity coefficient
3rd level: A metal disk with an unknown thermal conductivity coefficient
4th level: Flow of water for cooling
The device if insulated so all the heat (ideally) flow from the resistor through the disks to the water.
The disks carry 2 thermocouples each to measure temp difference at given distance for each
You use the 1st disk to calculate the heat flow (known length, area, coefficient, temp difference)
The heat flow in the 2nd disk is the same as the one in the 1st
You calculate 2nd disk's coefficient using the same formula (known heat flow, length, area, temp difference)
My question is: What happens if the 2nd disk's length (the one with the unknown coefficient) is reduced? Since Q= - λ A ΔΤ / d and λ, Α are definite constants, either ΔΤ or Q with change. My guess is both. The out temp of the will rise (will be closer to the in temp) AND the heat flow will be more (the heat will transfer faster)
The apparatus is this
1st level: A resistor to produce heat
2nd level: A metal disk with known thermal conductivity coefficient
3rd level: A metal disk with an unknown thermal conductivity coefficient
4th level: Flow of water for cooling
The device if insulated so all the heat (ideally) flow from the resistor through the disks to the water.
The disks carry 2 thermocouples each to measure temp difference at given distance for each
You use the 1st disk to calculate the heat flow (known length, area, coefficient, temp difference)
The heat flow in the 2nd disk is the same as the one in the 1st
You calculate 2nd disk's coefficient using the same formula (known heat flow, length, area, temp difference)
My question is: What happens if the 2nd disk's length (the one with the unknown coefficient) is reduced? Since Q= - λ A ΔΤ / d and λ, Α are definite constants, either ΔΤ or Q with change. My guess is both. The out temp of the will rise (will be closer to the in temp) AND the heat flow will be more (the heat will transfer faster)